Merge pull request #549 from python-cmd2/instance_attributes

Convert aliases from a class attribute to an instance attribute

Author: tleonhardt

cmd2/cmd2.py

@@ -307,7 +307,6 @@ class Cmd(cmd.Cmd):
     # Attributes used to configure the StatementParser, best not to change these at runtime
     multiline_commands = []
     shortcuts = {'?': 'help', '!': 'shell', '@': 'load', '@@': '_relative_load'}
-    aliases = dict()
     terminators = [';']
 
     # Attributes which are NOT dynamically settable at runtime
@@ -386,6 +385,9 @@ def __init__(self, completekey: str='tab', stdin=None, stdout=None, persistent_h
         # Commands to exclude from the history command
         self.exclude_from_history = '''history edit eof eos'''.split()
 
+        # Command aliases
+        self.aliases = dict()
+
         self._finalize_app_parameters()
 
         self.initial_stdout = sys.stdout